Satellite imagery shows Iran burying and reinforcing key nuclear facilities with concrete, soil and upgraded air defenses, as US military pressure grows and diplomatic talks continue over Tehran’s nuclear programme.
Iran is racing to shield key nuclear facilities beneath concrete and earth, transforming them into hardened bunkers as US military pressure builds in the region, according to new satellite analysis by the Institute for Science and International Security.
The Washington-based nonproliferation watchdog said high-resolution imagery shows rapid efforts to bury and reinforce sensitive sites, raising fresh concerns about Tehran’s nuclear ambitions even as diplomatic talks continue.
Over the “last two to three weeks, Iran has been busy burying the new Taleghan 2 facility at the Parchin military complex with soil,” the institute said in its latest assessment.
CONCRETE SARCOPHAGUS AT PARCHIN
At the Taleghan 2 facility inside the Parchin military complex, about 30 kilometers southeast of Tehran, satellite imagery from February 13 shows a completed concrete shell around the main structure. Soil is now being piled over it.
“The facility may soon become a fully unrecognisable bunker, providing significant protection from aerial strikes,” warned ISIS president David Albright.
Imagery indicates that once the concrete sarcophagus hardened, “Iran did not hesitate to move soil over large parts of the new facility.” Earth piles accumulating on nearby hills are likely intended to further bury the structure, leaving only limited entrance portals visible.
The site is enclosed by high security walls. A concrete batch plant inside the perimeter appears dedicated to ongoing fortification.
The institute said the new construction signals “the strategic importance of the facility to the Iranian regime,” though its precise purpose cannot be determined from imagery alone.
TUNNELS HARDENED NEAR NATANZ
Additional satellite images from February 10 show efforts to harden tunnel entrances under Kolang-Gaz La Mountain, roughly two kilometers from the Natanz nuclear facility.
Concrete is being poured over an extended western tunnel entrance. At an eastern portal, rock and soil have been pushed back and leveled to allow additional overburden — extra layers of rock, soil or concrete to absorb the force of potential airstrikes.
“These efforts strengthen the tunnel portals and provide additional protection against an airstrike,” the institute said.
Smaller closed-roof vehicles have also been observed near the entrances, suggesting interior outfitting may be underway. In the past, Iran linked construction there to rebuilding an advanced centrifuge assembly plant. However, the size of the complex and its mountain cover “raised immediate concern whether additional sensitive activities are planned, such as uranium enrichment.”
CONCEALMENT AT ESFAHAN
At the Esfahan nuclear complex, another enrichment site previously bombed by the United States, imagery from February 8 shows apparent efforts to conceal tunnel entrances.
The effectiveness of these measures against powerful airstrikes remains unclear based on existing intelligence.
AIR DEFENSES REACTIVATED
Since last year’s conflict, active defenses at Parchin have also been upgraded. Iran reactivated an abandoned anti-aircraft artillery site in July 2025 and added two new anti-aircraft positions in July and August.
The installed systems appear to be anti-aircraft artillery, further reinforcing the defensive posture around the site.
The institute noted that Parchin historically played a role in nuclear weapons–related work during Iran’s Amad Plan, including neutron initiator development and multipoint initiation experiments up to at least 2004.
While negotiations between Washington and Tehran continue — with US officials expecting fresh proposals from Iran in the coming weeks — the satellite imagery suggests Tehran is simultaneously fortifying infrastructure tied to its nuclear programme.
The construction, the institute concluded, indicates “its strategic significance,” even if its ultimate function remains uncertain.
With inputs from agencies
